Healthcare is notoriously slow to adopt evidence-based practices (EBPs). This proposal serves the long-term goal of developing a model for promoting the adoption of EBPs in primary care. The objective of this project is to develop and apply such a model to an urgent public health problem: the prescription opioid crisis. Over the past decades, opioids have been used increasingly to treat chronic non-cancer pain. This change in practice has been accompanied by alarming increases in prescription opioid misuse, addiction, and diversion. This work prepares for a subsequent randomized trial that will test the new model against other methods used to promote EBP adoption in primary care. The proposed model is called NIATx-VOP (the Network for Improvement of Addiction Treatment approach to reducing Variation in Opioid Prescribing). NIATx-VOP is designed to improve adherence to clinical guidelines for opioid prescribing. NIATx-VOP builds upon NIATx, a proven method of quality improvement that applies systems engineering principles to addiction treatment. To this approach, the proposal adds an implementation strategy consisting of three innovations: (1) a process for translating clinical guidelines into a checklist-based implementation guide for clinicians, (2) a physician peer coaching model, and (3) implementation support using tools from systems engineering. The standard approach to improving medical practice involves experts producing clinical guidelines based on scientific evidence, and such a guideline has been developed for opioid prescribing for chronic non-cancer pain. This guideline has not been widely implemented in primary care. This project will team the experts who developed the guideline for opioid prescribing with experts in implementation science and primary care to translate the guideline into an actionable, checklist-based implementation guide. Coaching has proven to be effective in improving process goals in healthcare, such as reducing waiting time; it has not yet been proven effective for clinical goals that involve physicians. Diffusion of innovations theory suggests that homophily-the likeness between change agents and those whose behavior they hope to change-may relate to this issue. A physician may be more likely to adopt changes recommended by a physician-coach than by the other healthcare providers who often work as coaches because physicians see physician-coaches as similar to themselves. Evidence also suggests that EBPs must be adapted to a specific context to succeed. In NIATx-VOP, physician coaches will learn tools from systems engineering to help primary care clinics adapt the checklist-based guideline into the workflow and procedures of a clinic. The proposed work consists of 3 specific aims. The first aim focuses on guideline translation and coach training, the second aim focuses on implementing NIATx-VOP in four primary care clinics, and the third aim assesses the feasibility and preliminary effectiveness of the approach using mixed methods. The strategy proposed here is significant because it has the potential to affect not only opioid prescribing but perhaps the adoption of EBPs throughout healthcare.